Tanada, using those screw-in circuit breakers that work as you described is illegal and extremely dangerous in every jurisdiction in the USA/Canada as they are NOT COMPLIANT with any National Electrical Code published since the 1970s.

BTW, what you described are "auto reset" thermal breakers, which are only usable in the USA in vehicular electrical systems, and are now banned in residences. (They never were legal in Canada.) They are not even a good idea in automobiles and trucks. When an overcurrent occurs, power needs to remain off until the fault is corrected.

The devices you showed a picture of are "manual reset" fuse replacements which trip after a prolonged overcurrent which as you noted, cooks the wires. Those breakers are reset manually by the black button in the center. Those that you showed pictures of are illegal in almost all jurisdictions, which require an Underwriters Laboratory and/or Canadian Safety Agency safety rating and marking - those are made in China and lack the UL/CSA markings.

The generic problem with fuse replacements is that older wiring is not the same as modern wiring which has insulation designed to tolerate the temporary overcurrent and to preserve insulating properties at higher temperatures. For example the Romex wire commonly used for residential wiring in wood-framed buildings:This wire has a temperature rating of 194 degrees F. That sounds like a lot, but it does not take a prolonged overcurrent to melt the wire insulation in an attic space that is already at 140 degrees F on a hot Summer day. The interior insulation is wrapped with brown Kraft paper which has been treated with Boric Acid or other fire retardants. Contrast these wires to the 70-100 year old wiring that one would find in a residence old enough to have screw-in fuses, which would likely have cotton-wrapped wires in a woven cotton jacket impregnated with now-100-year old oil-based enamel. Otherwise known as kindling.Which is why I am a believer in metallic conduits with metallic junction boxes that contain fire, when I spec my new house for construction. Except outside where for trench burial I favor plastic conduits that will not conduct massive amounts of electricity into the residence itself from nearby lightning strikes.

The painful truth: if you are experiencing an excessive amount of fuse replacements, you need to have an Electrician rewire all or a portion of your house, and eliminate the overloaded circuits. A total re-wire with modern wiring and a modern circuit breaker panel is the ideal corrective action. If you cannot afford to do that, you need to stick with the original fast-acting fuses.

Sorry to go all "EE" on you, but professional ethics will not allow me to pass when somebody is giving bad advice that potentially could harm others when followed.

Come on KJ...I was about to thank Tanada for a great idea. I guess that's why I have never seen those before The old 30 amp fuses will do...I have never popped a fuse since I lived here. But I am an energy miser.

Yes, my house has kindling in the wiring. Kind of makes you wonder what they were thinking. But as I moved each circuit to the CL breaker panel I replaced wires with Romex. The ceiling lights and bedroom outlets are still old wires and on the old fusebox. But they are low load as well. And I plan to just leave them there. I am back-feeding the old fusebox from a circuit in the critical loads panel so it is all powered by the solar/battery inverter.

I'm more concerned with the Lithium battery bursting into flames than the wiring You think I should put it outside?

A Solar fuel spill is otherwise known as a sunny day!The energy density of a tank of FF's doesn't matter if it's empty.https://monitoringpublic.solaredge.com/solaredge-web/p/kiosk?guid=19844186-d749-40d6-b848-191e899b37db

I think you should keep an expensive Lithium battery in a conditioned or partially conditioned space inside a metallic enclosure. It does not vent hydrogen like wet acid cells do, but it does get really hot from an internal short in one of the cells. That is the real reason a Tesla sedan weighs over 4k pounds, because Elon Musk understands that and wraps each cell in steel, and cools the battery. An attached garage would be a good spot, if it shares at least one wall with heated or A/C'd space. That would be the wall to choose to mount the battery. I believe if you look, you might find an online Tesla PowerWall manual that answers all your questions.

Most modern wiring is quite OK if used at its power rating .On the whole I would rather favor apparent wiring kept away from thermal insulation and cooled by natural convexion if the wiring is buried under thermal insulation it's a disaster waiting to happen we have Thermal overloads here , it's quite acceptable ,also having the 230 volts international standard help with the current , as I said above Earth leakage protection IS compulsory

sparky wrote:Most modern wiring is quite OK if used at its power rating .On the whole I would rather favor apparent wiring kept away from thermal insulation and cooled by natural convexion if the wiring is buried under thermal insulation it's a disaster waiting to happen we have Thermal overloads here , it's quite acceptable ,also having the 230 volts international standard help with the current , as I said above Earth leakage protection IS compulsory

The original house wiring from the early 1900's pre-dates the widespread use of insulation. It is called "Knob and Tube":Wherever it passes through wood, they insulated with a ceramic tube. It was secured to wood with insulating ceramic knobs. I have found it still in use in old houses, although the wires by then were bare, the cotton or linen having crumbled or been gnawed away by rodents. It is amongst the most dangerous of wiring, and it's also a source of asbestos, added to the cloth insulation to increase resistance to heat. It and all 2-wire, ungrounded receptacles and electric lighting should be upgraded and made safe.

My personal experience is mostly in specifying power for computer rooms, which can get very interesting in Brownstone buildings and Victorian-era offices.

Wow, you could get up close and personal with those wires. Just put alligator clips on the load and hook up anywhere.

Of course you're right KJ, manuals are wonderful things. I have downloaded Gbytes of manuals as I proceed.

Unfortunately Tesla has cancelled production of the DC coupled Powerwall. They are concentrating on AC coupled. This allows the Powerwall to be backfit into an existing grid-tied PV system or used purely as a grid backup. The price is the same but the AC unit includes a 5kw inverter/charger and a controllable transfer switch.

This is fine for Tesla's business, but not the most efficient way to implement a battery based PV system from scratch. There are losses incurred in the DC-AC-DC charging circuit. There are two inverters instead of one, which causes communications and control issues. And if the batteries die completely you have to have a grid to restart the system as well as to commission the system. This will not meet my requirements so I am going to use an LG Chem DC coupled 10 kw-hr battery. This is compatible with my Solaredge Storedge 7600 multimode inverter. https://solaredge.com/products/storedge#/

The Storedge inverter has an integrated charge controller operating around 400vdc which matches the PV voltage and charges the 400v battery directly. With the usage meter I can control grid vs PV vs battery and develop any control scheme I want. The inverter will produce a constant 7500 watts and charge the batteries at a 5000 watt rate, which is their limit. Running on batteries it will produce a constant 5000 watts. The transition between PV, battery, and grid is seamless. And I have complete monitoring from anywhere in the world. In fact I can make the monitoring portal available to the public if I want. So I might give you all a peek

Last edited by baha on Tue 21 Mar 2017, 06:51:04, edited 1 time in total.

A Solar fuel spill is otherwise known as a sunny day!The energy density of a tank of FF's doesn't matter if it's empty.https://monitoringpublic.solaredge.com/solaredge-web/p/kiosk?guid=19844186-d749-40d6-b848-191e899b37db

BTW - I have already purchased the PV equipment and installed the AC side. I am getting it wholesale so I have spent about $7500 so far. That's for a complete 6.7 kw PV system. The only remaining outlays are the battery and the equipment rental for the ground mount. I expect to bring this in under $13k. I will get 30% rebate from you guys so the final will be under $10k. A little over $1/watt for a battery based, fully off-grid capable, PV system that will run my entire house for at least 10 years and maybe 25. This is what you get for jumping in with both feet.

I have decided since you all have helped me pay for this I will magnanimously give my excess power to Duke energy. Until the electric VW is complete

A Solar fuel spill is otherwise known as a sunny day!The energy density of a tank of FF's doesn't matter if it's empty.https://monitoringpublic.solaredge.com/solaredge-web/p/kiosk?guid=19844186-d749-40d6-b848-191e899b37db

KaiserJeep wrote:The original house wiring from the early 1900's pre-dates the widespread use of insulation. It is called "Knob and Tube":Wherever it passes through wood, they insulated with a ceramic tube. It was secured to wood with insulating ceramic knobs. I have found it still in use in old houses, although the wires by then were bare, the cotton or linen having crumbled or been gnawed away by rodents. It is amongst the most dangerous of wiring, and it's also a source of asbestos, added to the cloth insulation to increase resistance to heat. It and all 2-wire, ungrounded receptacles and electric lighting should be upgraded and made safe.

My personal experience is mostly in specifying power for computer rooms, which can get very interesting in Brownstone buildings and Victorian-era offices.

I grew up in a farmhouse my great grandfather built in 1911 that was wired during the 'rural electrification' campaign of the FDR Administration in the 1930's. Everything was knob and tube wiring right up until my father remodeled the two front porches into enclosed rooms around 1979 and replaced the master fusebox with a breaker panel. From then until about 2005 the house was rewired in stages, but when I sold it in 2013 as executor of his estate it still had a 4 circuit fusebox that powered the second floor bedrooms. The only room upstairs that fed directly into the breaker box was the bathroom, which was completely gutted, rewired and replumbed around 2005. You could still go upstairs to the third floor/attic and trace the knob and tube wiring through the floor joists which were exposed. The people who wired it originally were not idiots, just as in the photo you posted they separated the wires in their tarpaper insulation by a good foot to 18 inches so that if a rat or other rodent chewed off the insulation they could not short across both wires by doing so.

Modern Americans have become so risk adverse it is sad, that house is over a century old and was still using portions of the original wiring for 70 years without ever having a fire and never having a significant short. It is not about the quality of the materials, it is about the quality of the workmanship used to install those materials. Was it hyper safe three wire grounded super insulated in metal conduit? Nope. Was it safe? Well 70 years of evidence says it was. And before you pop off about exceptions none of the other farmhouses in the area built and wired the same way were suddenly bursting into flames either. If they had been nobody would have trusted electricity in their homes.

I should be able to change a diaper, plan an invasion, butcher a hog, design a building, write, balance accounts, build a wall, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, pitch manure, program a computer, cook, fight efficiently, die gallantly. Specialization is for insects.

Tanada wrote:Modern Americans have become so risk adverse it is sad, that house is over a century old and was still using portions of the original wiring for 70 years without ever having a fire and never having a significant short. It is not about the quality of the materials, it is about the quality of the workmanship used to install those materials. Was it hyper safe three wire grounded super insulated in metal conduit? Nope. Was it safe? Well 70 years of evidence says it was. And before you pop off about exceptions none of the other farmhouses in the area built and wired the same way were suddenly bursting into flames either. If they had been nobody would have trusted electricity in their homes.

This is something I am in total agreement with. Our tolerance for risk has fallen below zero. We now use 800 page electrical codes, and thousands of pages of fire codes to try to eliminate that last small percentage of risk, but all we really accomplish is to empower the bureaucrats who write and enforce the regulations. We protect the idiot who uses a curling iron in the bath with a GFCI, but that doesn't really address the problem. We need more idiot education, and the ability to let them finish themselves off it they refuse to be educated. Quality work needs guidelines, but those guidelines should be inbuilt from the very first day of apprenticeship, in my opinion.

"It don't make no sense that common sense don't make no sense no more"
John Prine

Tanada, as rationalizations, your comments are classic. Knob and Tube originated in Edison's era and was in fact the safest wiring practice of the time, which was more than a century ago. I guarantee that in whatever size "area" you have in mind, the number of residential fires was not zero, and even today with our "hyper safer wiring" as you call it, electricity is the largest single cause of structure fires.

Yet your personal experience, with a sample size of ONE HOUSE, leads you to conclude that they are safe. That is bad logic and an incorrect conclusion. The judgements about "safe" and "unsafe" wiring practices, appliance design, and the materials used to bring this about are made by organizations such as Underwriter's Laboratory, a non-profit founded by the insurance companies who were paying off fire and accidental death claims from residential fires. The UL has more than any other group, caused the relatively unsafe wiring practices used by Edison to evolve into modern wiring. THEIR sample size is millions of residences and hundreds of thousands of residential fires.

Now I'll share a dirty little secret. The most stringent wiring requirements are found in commercial office and multiunit housing buildings, not private residences. These commercial structures have the metallic conduit and specified equipment quality levels needed to avoid a "mass casualty event" such as a structure fire that starts at the base of a multi-story building and burns up to the roof. The UL, or more exactly the insurance companies that fund the UL, have made a cold calculation about what level of risk THEY will tolerate with YOUR family. The NEC and the various building code provisions set the MINIMUM safety level, and it's far from "hyper safe wiring". It's only safe enough to strike a balance between "too expensive" for cheap building code compliant structures, and "safe enough" to keep enough of the paying insurance customers alive by minimizing the number of claims.

Here's a little test for you. Go down to your local homecenter store and go into the electrical section. There you will see many different examples of the common 3-prong "duplex receptacle".The above image is a device WITH a UL marking and is labelled as "specification grade". That means that it is just good enough to comply with all the local building codes, and probably costs less than $2.This is the best grade that you can buy at a common homecenter or electrical supply. It is called "hospital grade" and is good enough to allow respirators and other lifesaving equipment to be plugged in. You can tell it from the trash by the green dot. Down the street from me, this version is $8.60.

Let me just say, I'm not building my "dream house" and putting in "spec grade" hardware, or going with the lowest electrical bidder. YOU are free to make whatever decisions that you think are appropriate for you and your family.

The most stringent electrical requirements I've found were on ships. MI cable and fittings suck, especially the old stuff.But I suppose you can't wait out on the front lawn till the fire trucks arrive, either.

"It don't make no sense that common sense don't make no sense no more"
John Prine

Hawkcreek wrote:The most stringent electrical requirements I've found were on ships. MI cable and fittings suck, especially the old stuff.But I suppose you can't wait out on the front lawn till the fire trucks arrive, either.

Actually, even marine standards are surpassed by aircraft wiring, most of which is aluminum. Both are more expensive than residential wiring.

Yet another example of how insurance companies have used the government to complicate our lives and take our money.

I appreciate and follow building and electrical codes most of the time As an engineer and physicist I understand the principles behind them and feel comfortable making my own decisions. Even thou a little zap every once in a while doesn't bother me, my wife would freak...so I follow electrical codes as much as possible.

Grounding is something that has been taken to an extreme level in the codes. Europe is nothing like the US for grounding. And ARC fault protection is a complete pain. I feel so safe...do I really need insurance?

As far as the Navy goes we had MIL-SPEC UYK-43 computers that were rated to operate under salt water for an hour without failure.

A Solar fuel spill is otherwise known as a sunny day!The energy density of a tank of FF's doesn't matter if it's empty.https://monitoringpublic.solaredge.com/solaredge-web/p/kiosk?guid=19844186-d749-40d6-b848-191e899b37db

If you really want to build safety into your house, go with 20 amp, commercial duplex receptacles, from any building supply for about $3. Then use 15 amp breakers with 12 gauge wire. The whole idea of the modern code seems to be to protect the wiring from heat buildup, so this would give an extra layer of safety for minimal cost. The 20 amp receptacles would allow direct attachment to the 12 gauge much easier than trying to use 12 gauge on a 15 amp receptacle (no eye twisting around screws). Much more bang for the buck. Much more safety than using EMT or rigid conduit in a residence, especially considering the most common cause of electrical faults I have seen in an industrial context is skinned insulation from pulling wire into a metallic conduit of box. This would probably be worse if using the typical residential installer that only knows romex. If you are doing the work yourself or money is no object, go for it.

Probably 90 % of appliances in a modern house don't even use the ground in a 3 prong receptacle. Look at your tv's, computers, etc. The shop is probably the largest point of use of grounded plugs, because of exposed metal in tools. But the GFCI is probably the most life saving device installed in any home, so I don't mind seeing a few wasted grounds.

And of course, the proper starting point is in the design stage. I have a friend who spent thousands installing cat 5 cable with multiple drops into every room of his dream house. I tried to tell him that wireless was on the way, but he had money to burn.Even he laughs about it now.

"It don't make no sense that common sense don't make no sense no more"
John Prine

Hawkcreek and baha, you seem equipped to make good choices, I'm not worried about you. Tanada is a smart lady, but seems to have not thought this one through.

As for marine wiring and equipment, I saw a lot in the USCG. I remember watching a sailboat owner start his auxilliary engine, which was a lump of rust that had obviously been submerged in salt water at least once. Rust flakes started falling off the engine as soon as it began to run. He got it to run and thus passed - but got a profane lecture from the CPO I was with.

People make bad choices all the time, and things like building codes, National Electrical Codes, and marine and aircraft safety regulations are for their own benefit.

Baha, I don't know about where you live. But here in Silly Valley you cannot sell a house without an inspection. During the inspection they will check for unpermitted additions and improvements, and require that any substandard work be brought up to local codes and inspected again and approved before the sale. You may have no plans to ever sell, but life throws you curve balls sometimes, and plans change.

We have home/realty inspections carried out by people with questionable abilities here too. I deal with real electrical inspectors all the time and know what they look for. My electrical improvements (at least) have all been permitted and inspected. My envelope improvements are under the skin never to be seen again...and not structural.

As I moved circuits I added grounds of course. The ceiling lights have no grounds. I defy some amateur home inspector to find that

As you said, I plan to die here. But not from electrical shock

Since my house will be powered directly by a multimode solar inverter, I will have a level of ARC fault protection not available to a common household. Any ARC anywhere in the DC or AC wiring will shut the inverter down instantly.

A Solar fuel spill is otherwise known as a sunny day!The energy density of a tank of FF's doesn't matter if it's empty.https://monitoringpublic.solaredge.com/solaredge-web/p/kiosk?guid=19844186-d749-40d6-b848-191e899b37db

Hawkcreek wrote:If you really want to build safety into your house, go with 20 amp, commercial duplex receptacles, from any building supply for about $3. Then use 15 amp breakers with 12 gauge wire. The whole idea of the modern code seems to be to protect the wiring from heat buildup, so this would give an extra layer of safety for minimal cost. The 20 amp receptacles would allow direct attachment to the 12 gauge much easier than trying to use 12 gauge on a 15 amp receptacle (no eye twisting around screws). Much more bang for the buck. Much more safety than using EMT or rigid conduit in a residence, especially considering the most common cause of electrical faults I have seen in an industrial context is skinned insulation from pulling wire into a metallic conduit of box. This would probably be worse if using the typical residential installer that only knows romex. If you are doing the work yourself or money is no object, go for it.

Probably 90 % of appliances in a modern house don't even use the ground in a 3 prong receptacle. Look at your tv's, computers, etc. The shop is probably the largest point of use of grounded plugs, because of exposed metal in tools. But the GFCI is probably the most life saving device installed in any home, so I don't mind seeing a few wasted grounds.

And of course, the proper starting point is in the design stage. I have a friend who spent thousands installing cat 5 cable with multiple drops into every room of his dream house. I tried to tell him that wireless was on the way, but he had money to burn.Even he laughs about it now.

In my garage in my present home (vintage 1984) you will find two of the hospital grade receptacles above, which ARE 20 amp rated, as the "T" shaped hole will accept a NEMA 5-20P plug:I installed these for my table saw and my arc welder, both nominally 15 amp devices, but which had a habit of tripping a 15 amp breaker in heavy use. My garage was already drywalled with the extra-thick drywall used in garages, so I ran surface mounted PVC conduits and used a seperate bare copper 10 guage wire for the ground, and black/white insulated 12 guage supply wires. One of the two circuits is usually connected to a large treadmill which would also trip 15 amp breakers. Problem solved for about $70, half of which was a dual 20-amp circuit breaker.

Note also that the left hand vertical slot in both the duplex receptacles is longer than the right, a so-called "polarised plug" will fit there. Any exposed metal on a modern appliance with a 2-wire plug must be bonded to the conductor on the left blade of the polarized plug, which is connected to the neutral (white) wire. All the neutrals and grounds are connected togather at your breaker box in a little busbar with multiple screws:This is a means of insuring that if the hot (black) wire shorts to exposed metal on the appliance, the breaker will trip rather than allow somebody who touches the metal to be shocked. LOTS of words could be written about grounding and wiring, but I think we beat this one to death.

KaiserJeep wrote:My garage was already drywalled with the extra-thick drywall used in garages, ........

Another good thing to mention - I used the 5/8 inch "Firebond" throughout my house, and doubled it in the equipment closets. This adds thermal mass to the conditioned part of the house, and gives a little more fire resistance.Better if you do it yourself though, cause installers will charge a lot to do a whole house with this. Heavy, and hard on the back. I know, my back still hurts.

"It don't make no sense that common sense don't make no sense no more"
John Prine

That's good for fire safety. You also need at least one "safe room" in the house with bullet resistent drywall:

The wife and I dumped about an extra $3000 when we remodelled the master bathroom doing that. Sometimes people wonder about the steel door with slide bolts that swings out into the bedroom, and the extra storage for weapons, food, water, and the emergency cell phone inside our master bath. We went for the double layer wallboard (conventional over bullet resistent) and went for Grade 4 protection which is rated for AK-47 rounds.

Nowadays the manufacurers make this easy. They cut the panels to your specified sizes on a water jet, and drill the holes for the screws. You plan for the seams between panels to fall in a stud cavity, and they supply a backer strip and hardware to join the panels. Then you cover the panels with regular drywall using construction adhesive, and use a bullet-resistent door. We armored three walls, the fourth is an exterior wall with stucco and a metal mesh "mud job" tile shower wall, I'm not worried about that.

I understand, you may live in an area where this is not required. But Silicon Valley is subject to home invasions, I have a safe room, an alarm system, IP-connected security cameras that cover the entire exterior of our home, and a 12-guage to discourage "varmints".

KaiserJeep wrote:That's good for fire safety. You also need at least one "safe room" in the house with bullet resistant drywall:.......................................................I understand, you may live in an area where this is not required. But Silicon Valley is subject to home invasions, I have a safe room, an alarm system, IP-connected security cameras that cover the entire exterior of our home, and a 12-guage to discourage "varmints".

That is a great idea too. If I lived in a high threat zone, I would probably do the same. Here at my place, I just have weapons within reach everywhere. But I live by myself, and don't have to worry about the safety of anyone else. As an old Marine, I'm probably a little "offensive" anyway.

"It don't make no sense that common sense don't make no sense no more"
John Prine